No. 2.
Chlorate of potash 20 parts.
Carbonate of strontia 8 „
Calomel 10 „
Shellac 2 „
Sulphur 3 „
Charcoal (fine) 1 part
The advantage of this composition is that it is not at all liable to
suffer from damp in winter. The carbonate of strontia is a salt not
deliquescent like the nitrate, and is, moreover, always to be had in a
state of fine powder. The colour procured by the above formula is not so
deep as that which the first composition will produce; but it is
especially beautiful when contrasted with an intense blue. If its
combustion should be thought too rapid, less of the chlorate of potash
may be employed. It is to be moistened with the solution of shellac.